1. Field of the Invention
The present invention relates to medical devices, and more particularly, to airway devices, such as tracheal tubes.
2. Description of the Related Art
This section is intended to introduce the reader to various aspects of art that may be related to the present invention which is described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
In the course of treating a patient, a tube or other medical device may be used to control the flow of air, food, fluids, or other substances into and/or out of the patient. For example, medical devices, such as tracheal tubes, may be used to control the flow of one or more substances into or out of a patient. In many instances, it is desirable to provide a seal between the outside of the tube or device and the interior of the passage in which the tube or device is inserted. In this way, substances can only flow through the passage via the tube or other medical device, allowing a medical practitioner to maintain control over the type and amount of substances flowing into and out of the patient.
Tracheal tubes may be used to control the flow of air or other gases through a patient's trachea. Such tracheal tubes may include endotracheal tubes and tracheostomy tubes. To seal these types of tracheal tubes, inflatable cuffs are sometimes associated with these tubes. When inflated, these cuffs generally expand into the surrounding trachea to seal the tracheal passage around the circumference of the tube. A high-quality seal against the tracheal passageway allows a ventilator to perform efficiently.
Generally, endotracheal tubes are available in a subset of sizes from which doctors may select the closest approximate size for a particular patient. The difference in tube sizes may generally reflect both differences in the length of the tube as well as different tube diameters. In particular, doctors may wish to select an endotracheal tube with an appropriate diameter in order to allow the tube to be easily inserted into the patient while providing the largest possible airway path for respiratory gases. For example, an endotracheal tube with too small a tube diameter may be associated with an increased work of breathing for the patient. Conversely, an endotracheal tube with too large a tube diameter presents certain disadvantages. For example, if the outer diameter of the endotracheal tube is too large, it can become difficult to navigate through the larynx and trachea. Thus, too large an endotracheal tube may increase the time it takes to intubate the patient. Also, a large endotracheal tube can prove somewhat uncomfortable for the patient. For instance, irritation of the tracheal walls can result from increased contact with the endotracheal tube.